US4702985A - Aminoalcohols as adjuvant for liquid electrostatic developers - Google Patents
Aminoalcohols as adjuvant for liquid electrostatic developers Download PDFInfo
- Publication number
- US4702985A US4702985A US06/856,392 US85639286A US4702985A US 4702985 A US4702985 A US 4702985A US 85639286 A US85639286 A US 85639286A US 4702985 A US4702985 A US 4702985A
- Authority
- US
- United States
- Prior art keywords
- liquid developer
- electrostatic liquid
- developer according
- electrostatic
- less
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/12—Developers with toner particles in liquid developer mixtures
- G03G9/13—Developers with toner particles in liquid developer mixtures characterised by polymer components
- G03G9/131—Developers with toner particles in liquid developer mixtures characterised by polymer components obtained by reactions only involving carbon-to-carbon unsaturated bonds
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/12—Developers with toner particles in liquid developer mixtures
- G03G9/135—Developers with toner particles in liquid developer mixtures characterised by stabiliser or charge-controlling agents
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G9/00—Developers
- G03G9/08—Developers with toner particles
- G03G9/12—Developers with toner particles in liquid developer mixtures
- G03G9/135—Developers with toner particles in liquid developer mixtures characterised by stabiliser or charge-controlling agents
- G03G9/1355—Ionic, organic compounds
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Liquid Developers In Electrophotography (AREA)
Abstract
Electrostatic liquid developer having improved charging characteristics comprising
(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,
(B) thermoplastic resin particles having an average by area particle size of less than 10 μm,
(C) nonpolar liquid soluble ionic or zwitterionic compound, and
(D) at least one aminoalcohol compound.
The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
Description
1. Technical Field
This invention relates to an electrostatic liquid developer having improved charging characteristics. More particularly this invention relates to an electrostatic liquid developer containing as a constituent an aminoalcohol compound.
2. Backround Art
It is known that a latent electrostatic image can be developed with toner particles dispersed in an insulating nonpolar liquid. Such dispersed materials are known as liquid toners or liquid developers. A latent electrostatic image may be produced by providing a photoconductive layer with a uniform electrostatic charge and subsequently discharging the electrostatic charge by exposing it to a modulated beam of radiant energy. Other methods are known for forming latent electrostatic images. For example, one method is providing a carrier with a dielectric surface and transferring a preformed electrostatic charge to the surface. Useful liquid toners comprise a thermoplastic resin and dispersant nonpolar liquid. Generally a suitable colorant is present such as a dye or pigment. The colored toner particles are dispersed in the nonpolar liquid which generally has a high-volume resistivity in excess of 10.sup. 9 ohm centimeters, a low dielectric constant below 3.0 and a high vapor pressure. The toner particles are less than 10 μm average by area size. After the latent electrostatic image has been formed, the image is developed by the colored toner particles dispersed in said dispersant nonpolar liquid and the image may subsequently be transferred to a carrier sheet.
Since the formation of proper images depends on the differences of the charge between the liquid developer and the latent electrostatic image to be developed, it has been found desirable to add a charge director compound to the liquid toner comprising the thermoplastic resin, dispersant nonpolar liquid and generally a colorant. Such liquid toners, while developing good quality images, still do not provide the quality images required for certain end uses, e.g., optimum machine performance in digital color proofing. As a result much research effort has been expended in providing new type charge directors and/or charging adjuvants for electrostatic liquid toners. Higher quality image development of latent electrostatic images is still desired.
It has been found that the above disadvantages can be overcome and improved electrostatic liquid developers prepared containing an ionic or zwitterionic compound soluble in nonpolar liquid which have stabilized conductivity and/or improved image quality on latent electrostatic images.
In the accompanying drawing forming a material part of this disclosure:
FIG. 1 is a plot of the conductivity (pmho/cm) of a control developer (no additive) and developers of the invention containing triethanol amine (TEA) or ethanolamine (EA) over a time period of 15 minutes.
FIG. 2 is a plot of the conductivity (pmho/cm) during a machine run over a time period of 15 minutes (Example 6) of a control developer (no additive) and two developers of the invention containing ethanolamine (EA) in amounts of 0.3g and 0.5g.
In accordance with this invention there is provided an electrostatic liquid developer having improved charging characteristics comprising
(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,
(B) thermoplastic resin particles having an average by area particle size of less than 10μm,
(C) nonpolar liquid soluble ionic or zwitterionic compound, and
(D) at least one aminoalcohol compound.
Throughout the specification the below-listed terms have the following meanings:
Nonpolar liquid soluble ionic or zwitterionic compounds (C) are referred to throughout as charge directors.
Aminoalcohol (D) means that there is both an amino functionality and hydroxyl functionality in one compound.
Conductivity is the conductivity of the developer measured in picomhos (pmho)/cm at 5 hertz and 5 volts.
The electrostatic liquid developer, as defined above comprises four primary components more specifically described below. Additional components, in addition to the four primary components, include but are not limited to: colorants such as pigments or dyes, which are preferably present, fine particle size oxides, metals, etc.
The dispersant nonpolar liquids (A) are, preferably, branched-chain aliphatic hydrocarbons and more particularly, Isopar ®-G, Isopar ®-H, Isopar ®-K, Isopar ®-L, Isopar ®-M and Isopar ®-V. These hydrocarbon liquids are narrow cuts of isoparaffinic hydrocarbon fractions with extremely high levels of purity. For example, the boiling range of Isopar ®-G is between 157° C. and 176° C., Isopar ®-H between 176° C. and 191° C., Isopar ®-K between 177° C. and 197° C., Isopar ®-L between 188° C. and 206° C., Isopar ®-M between 207° C. and 254° C. and Isopar ®-V between 254.4° C. and 329.4° C. Isopar ®-L has a mid-boiling point of approximately 194° C. Isopar ®-M has a flash point of 80° C. and an auto-ignition temperature of 338° C. Stringent manufacturing specifications, such as sulphur, acids, carboxyl, and chlorides are limited to a few parts per million. They are substantially odorless, possessing only a very mild paraffinic odor. They have excellent odor stability and are all manufactured by the Exxon Corporation. High-purity normal paraffinic liquids, Norpar ®12, Norpar ®13 and Norpar ®15, Exxon Corporation, may by used. These hydrocarbon liquids have the following flash points and auto-ignition temperatures:
______________________________________
Auto-Ignition
Liquid Flash Point (°C.)
Temp (°C.)
______________________________________
Norpar ® 12
69 204
Norpar ® 13
93 210
Norpar ® 15
118 210
______________________________________
All of the dispersant nonpolar liquids have an electrical volume resistivity in excess of 109 ohm centimeters and a dielectric constant below 3.0. The vapor pressures at 25° C. are less than 10 Torr. Isopar ®-G has a flash point, determined by the tag closed cup method, of 40° C., Isopar ®-H has a flash point of 53° C. determined by ASTM D 56. Isopar ®-L and Isopar ®-M have flash points of 61° C., and 80° C., respectively, determined by the same method. While these are the preferred dispersant nonpolar liquids, the essential characteristics of all suitable dispersant nonpolar liquids are the electrical volume resistivity and the dielectric constant. In addition, a feature of the dispersant nonpolar liquids is a low Kauri-butanol value less than 30, preferably in the vicinity of 27 or 28, determined by ASTM D 1133. The ratio of thermoplastic resin to dispersant nonpolar liquid is such that the combination of ingredients becomes fluid at the working temperature.
Useful thermoplastic resins or polymers include: ethylene vinyl acetate (EVA) copolymers (Elvax ®resins, E. I. du Pont de Nemours and Company, Wilmington, DE), copolymers of ethylene and and α,β-ethylenically unsaturated acid selected from the class consisting of acrylic acid and methacrylic acid, copolymers of ethylene (80 to 99.9%)/acrylic or methacrylic acid (20 tp 0%)/alkyl (C1 to C5) ester of methacrylic or acrylic acid (0 to 20%), polyethylene, polystyrene, isotactic polypropylene (crystalline), ethylene ethyl acrylate series sold under the trademark Bakelite ® DPD 6169, DPDA 6182 Natural and DTDA 9169 Natural by Union Carbide Corp., Stamford, CN; ethylene vinyl acetate resins, e.g., DQDA 6479 Natural and DQDA 6832 Natural 7 also sold by Union Carbide Corp.; Surlyn ® ionomer resin by E. I. du Pont de Nemours and Company, Wilmington DE, etc. Preferred copolymers are the copolymer of ethylene and an α,β-ethylenically unsaturated acid of either acrylic acid or methacrylic acid. The synthesis of copolymers of this type are described in Rees U.S. Pat. No. 3,264,272, the disclosure of which is incorporated herein by reference. For the purposes of preparing the preferred copolymers, the reaction of the acid containing copolymer with the ionizable metal compound, as described in the Rees patent, is omitted. The ethylene constituent is present in about 80 to 99.9% by weight of the copolymer and the acid component in about 20 to 0.1% by weight of the copolymer. The acid numbers of the copolymers range from 1 to 120, preferably 54 to 90. Acid No. is milligrams potassium hydroxide required to neutralize 1 gram of polymer. The melt index (g/10 min) if 10 to 500 is determined by ASTM D 1238 Procedure A. Particularly preferred copolymers of this type have an acid number of 66 and 60 and a melt index of 100 and 500 determined at 190° C., respectively.
In addition, the resins have the following preferred characteristics:
1. Be able to disperse the colorant, e.g., pigment.
2. Be insoluble in the dispersant liquid at temperatures below 40° C., so that the resin will not dissolve or solvate in storage.
3. Be able to solvate at temperatures above 50° C.,
4. Be able to be ground to form particles between 0.1 μm and 5μm, in diameter,
5. Be able to form a particle (average by area) of less than 10 μm, e.g., determined by Horiba CAPA-500 centrifugal automatic particle analyzer, manufactured by Horiba Instruments, Inc., Irvine, CA: solvent viscosity of 1.24 cps, solvent density of 0.76 g/cc, sample density of 1.32 using a centrifugal rotation of 1,000 rpm, a particle size range of 0.01 to less than 10μm, and a particle size cut of 1.0 μm.
6. Be able to fuse at temperatures in excess of 70° C. By solvation in 3. above, the resins forming the toner particles will become swollen or gelatinous.
Suitable nonpolar liquid soluble ionic or zwitterionic compounds (C), which are used in an amount of 1 to 1000 mg/g, preferably 1 to 100 mg/g developer solids, include: positive charge directors, e.g., sodium dioctylsulfosuccinate (manufactured by American Cyanamid Co.), zirconium octoate and metal soaps such as copper oleate, etc.; negative charge directors, e.g., lecithin, Basic Calcium Petronate ®, Basic Barium Petronate ® oil-soluble petroleum sulfonate, manufactured by Sonneborn Division of Witco Chemical Corp., New York, NY, alkyl succinimide (manufactued by Chevron Chemical Company of California), etc.
The fourth component of the electrostatic liquid developer is at least one aminoalcohol (D), preferably thoroughly dispersed throughout the developer. Examples of this type compound include: triisopropanolamine, triethanolamine, ethanolamine, 3-amino-1-propanol, o-aminophenol, 5-amino-1-petanol, tetra(2-hydroxyethyl)ethylene diamine, etc. The aminoalcohol is used in an amount of 1 to 1000 mg/g, preferably 1 to 100 mg/g developer solids.
Components (A) and (B) are present in the electrostatic liquid developer in the following amounts.
Component (A): 99.9 to 85% by weight, preferably 99.5 to 98% by weight; and
Component (B): 0.1 to 15% by weight, preferably 0.5 to 2% by weight. The amounts of components (C) and (D) in the developer are set out above and are not included in considering weight of developer solids.
As indicated above, additional components that can be present in the electrostatic liquid developer are colorants, such as pigments or dyes and combinations thereof, are preferably present to render the latent image visible, though this need not be done in some applictions. The colorant, e.g., a pigment, may be present in the amount of up to about 60 percent by weight or more based on the weight of the resin. The amount of colorant may vary depending on the use of the developer. Examples of pigments are Monastral ® Blue G (C.I. Pigment Blue 15 C.I. No. 74160), Toluidine Red Y (C.I. Pigment Red 3), Quindo ® Magenta (Pigment Red 122). Indo ® Brilliant Scarlet (Pigment Red 123, C.I. No. 71145), Toluidine Red B (C.I. Pigment Red 3), Watchung ® Red B (C.I. Pigment Red 48), Permanent Rubine F6B13-1731 (Pigment Red 184), Hansa ® Yellow (Pigment Yellow 98), Dalamar ® Yellow (Pigment Yellow 74, C.I. No. 11741), Toluidine Yellow G (C.I. Pigment Yellow 1), Monastral ® Blue B (C.I. Pigment Blue 15), Monastral ® Green B (C.I. Pigment Green 7), Pigment Scarlet (C.I. Pigment Red 60), Auric Brown (C.I. Pigment Brown 6), Monastral ® Green G (Pigment Green 7), Carbon Black, Cabot Mogul L (black pigment C.I. No. 77266) and Stirling NS N 774 (Pigment Black 7, C.I. No. 77266).
Fine particle size oxides, e.g., silica, alumina, titania, etc,; preferably in the order of 0.5 μm or less can be dispersed into the liquefied resin. These oxides can be used alone or in combination with the colorants. Metal particles can also be added.
The percent pigment in the thermoplastic resin is 1% to 60% by weight, preferably 1 to 30% by weight.
The particles in the electrostatic liquid developer have an average by area particle size of less than 10 μm, preferably the average by area particle size is less than 5 μm. The resin particles of the developer may or may not be formed having a plurality of fibers integrally extending therefrom although the formation of fibers extending from the toner particles is preferred. The term "fibers" as used herein means pigmented toner particles formed with fibers, tendrils, tentactles, threadlets, fibrils, ligaments, hairs, bristles, or the like.
The electrostatic liquid developer can be prepared by a variety of processes. For example, into a suitable mixing or blending vessel, e.g., attritor, heated ball mill, heated vibratory mill such as a Sweco Mill manufactured by Sweco Co., Los Angeles, CA, equipped with particulate media for dispersing and grinding, Ross double planetary mixer manufactured by Charles Ross and Son, Hauppauge, NY, etc., are placed the above-described ingredients. Generally the resin, dispersant nonpolar liquid and optional colorant are placed in the vessel prior to starting the dispersing step although after homogenizing the resin and the dispersant nonpolar liquid the colorant can be added. Polar additive can also be present in the vessel, e.g., 1 to 99% based on the weight of polar additive and dispersant nonpolar liquid. The dispersing step is generally accomplished at elevated temperature, i.e., the temperature of ingredients in the vessel being sufficient to plasticize and liquefy the resin but being below that at which the dispersant nonpolar liquid or polar additive, if present, degrades and the resin and/or colorant decomposes. A preferred temperature range is 80° to 120° C. Other temperatures outside this range may be suitable, however, depending on the particular ingredients used. The presence of the irregularly moving particulate media in the vessel is preferred to prepare the dispersion of toner particles. Other stirring means can be used as well, however, to prepare dispersed toner particles of proper size, configuration and morphology. Useful particulate media are particulate materials, e.g., spherical, cylindrical, etc. taken from the class consisting of stainless steel, alumina, ceramic, zirconium, silica, and sillimanite. Carbon steel particulate media is useful when colorants other than black are used. A typical diameter range for the particulate media is in the range of 0.04 to 0.5 inch (1.0 to ˜13 mm).
After dispersing the ingredients in the vessel with or without a polar additive present until the desired dispersion is achieved, typically 1 hour with the mixture being fluid, the dispersion is cooled, e.g., in the range of 0° C. to 50° C. Cooling may be accomplished, for example, in the same vessel, such as the attritor, while simultaneously grinding in the presence of additional liquid with particulate media to prevent the formation of a gel or solid mass; without stirring to form a gel or solid mass, followed by shredding the gel or solid mass and grinding, e.g., by means of particulate media in the presence of additional liquid; or with stirring to form a viscous mixture and grinding by means of particulate media in the presence of additional liquid. Additional liquid means dispersant nonpolar liquid, polar liquid or combinations thereof. Cooling is accomplished by means known to those skilled in the art and is not limited to cooling by circulating cold water or a cooling material through an external cooling jacket adjacent the dispersing apparatus or permitting the dispersion to cool to ambient temperature. The resin precipitates out of the dispersant during the cooling. Toner particles of average particle size (by area) of less than 10 μm, as determined by a Horiba CAPA-500 centrifugal particle analyzer described above or other comparable apparatus, are formed by grinding for a relatively short period of time.
After cooling and separating the dispersion of toner particles from the particulate media, if present, by means known to those skilled in the art, it is possible to reduce the concentration of the toner particles in the dispersion, impart an electrostatic charge of predetermined polarity to the toner particles, or a combination of these variations. The concentration of the toner particles in the dispersion is reduced by the addition of additional dispersant nonpolar liquid as described previously above. The dilution is normally conducted to reduce the concentration of toner particles to between 0.1 to 3 percent by weight, preferably 0.5 to 2 weight percent with respect to the dispersant nonpolar liquid. One or more nonpolar liquid soluble ionic or zwitterionic compounds, of the type set out above, can be added to impart a positive or negative charge, as desired. The addition may occur at any time during the process. If a diluting dispersant nonpolar liquid is also added, the ionic or zwitterionic compound can be added prior to, concurrently with, or subsequent thereto. If the aminoalcohol compound has not been previously added in the preparation of the developer, it can be added subsequent to the developer being charged. Preferably the aminoalcohol compound is present during the dispersing step. A preferred mode of the invention is described in Example 10.
The electrostatic liquid developers of this invention demonstrate improved charging qualities such as improved stabilized conductivity over liquid toners containing standard charge directors or other known additives. The developers of this invention are useful in copying, e.g., making office copies of black and white as well as various colors; or color proofing, e.g., a reproduction of an image using the standard colors: yellow, cyan, magenta together with black as desired. In copying and proofing the toner particles are applied to a latent eletrostatic image.
Other uses are envisioned for the electrostatic liquid developers include: digital color proofing, lithographic printing plates, and resists.
The following examples wherein the parts and percentages are by weight, illustrate but do not limit the invention. In the examples, the melt indices were determined by ASTM D 1238, Procedure A, the average particle sizes by area were determined by a Horiba CAPA-500 centrifugal particle analyzer as described above, conductivities were measured in picomhos (pmho)/cm at five hertz and low voltage, 5.0 volts, and the densities were measured using a Macbeth densitometer model RD 918. Resolution is expressed in the Examples in line pairs/mm (1p/mm). The aminoalcolhol additive used in the Examples have the following designations:
TIPA=triisopropanolamine, Aldrich Chemical Co., Milwaukee, WI, 95%
TEA=triethanolamine, Aldrich Chemical Co., Milwaukee, WI
EA=ethanolamine, Eastman Kodak, Rochester, New York, 98%
3-AP=3-amino-1-propanol, Aldrich Chemical Co., Milwaukee, WI, 99%
o-APh=o-aminophenol, Aldrich Chemical Co., Milwaukee, WI, 99%
5-AP=5-amino-1-pentanol, Aldrich Chemical Co., Milwaukee, WI, 97%
In a Union Process 1-S Attritor, Union Process Company, Akron, Ohio, was placed the following ingredients:
______________________________________
Ingredient Amount (g)
______________________________________
Copolymer of ethylene (89%)
200
and methacrylic acid (11%),
melt index at 190° C. is 100,
Acid No. is 66
Heucophthal Blue G XBT-583D,
14
Heubach, Inc., Newark, NJ
L. nonpolar liquid having a
1000
Kauri-butanol value of 27, Exxon
Corporation
______________________________________
The ingredients were heated to 100° C.±10° C. and milled at a rotor speed of 230 rpm with 0.1875 inch (4.76 mm) diameter stainless steel balls for one hour. The attritor was cooled to room temperature while the milling was continued and then 700 grams of Isopar ®-H, nonpolar liquid having a Kauri-butanol value of 27. Exxon Corporation, were added. Milling was continued at a rotor speed of 330 rpm for 24 hours to obtain toner particles with an average size of 1.2 μm by area. The particulate media were removed and the dispersion of toner particles was then diluted to 1.5 percent solids with additional Isopar ®-H. To 1500 grams of the 1.5 percent material was added 40 grams of a 5.5% solution (diluted from 55% with Isopar ®-H) of Basic Barium Petronate ® oil-soluble petroleum sulfonate, Sonneborn Division of Witco Chemical Corp., New York, New York, and the specified amount of additive. Image quality was determined using a Savin 870 copier at standard mode: charging corona set at 6.8 kv and transfer corona set at 8.0 kv using as a carrier sheet Plainwell offset enamel paper, number 3 gloss, 60 lb. test, Plainwell Paper Co., Plainwell, Mi. The extended runs were conducted by running the machine in standard mode except that the paper feed was disconnected and a totally black target was used. The results are shown in Table 1.
TABLE 1
______________________________________
Con- Trans-
duc- Reso- fer
tiv- Den- lu- Effi-
Additive
Amount.sup.a
Time.sup.b
ity sity tion ciency
______________________________________
none -- 0 71 0.82 3 94%
15 24 1.17 7 88%
TIPA 0.5 0 60 1.42 10 72%
15 64 1.11 10 72%
TEA 0.1 0 70 1.37 9 91%
15 77 1.01 9 94%
EA 0.5 0 60 1.65 10 94%
15 80 1.17 11 90%
3-AP 0.5 0 50 1.38 9 84%
15 60 1.15 11 75%
o-APh 0.5 0 61 1.12 6 92%
15 61 1.22 8 80%
5-AP 0.5 0 64 0.96 10 75%
15 52 0.92 6 67%
______________________________________
.sup.a gram
.sup.b minutes
In a Union Process 1-S Attritor, Union Process Company, Akron, Ohio was placed the following ingredients:
______________________________________
Ingredient Amount (g)
______________________________________
Copolymer of ethylene (89%)
200
and methacrylic acid (11%),
melt index at 190° C. is 100,
Acid No. is 66
Monastral ® Blue BT 383D
22
L, nonpolar liquid having a
1000
Kauri-butanol value of 27, Exxon
Corporation
______________________________________
The ingredients were heated to 100° C.±10° C. and milled at a rotor speed of 230 rpm with 0.1875 inch (4.76 mm) diameter stainless steel balls for two hours. The attritor was cooled to room temperature while the milling was continued and then 700 grams of Isopar ®-H, nonpolar liquid having a Kauri-butanol value of 27, Exxon Corporation, was added. Milling was continued at a rotor speed of 330 rpm for three hours to obtain toner particles with an average size of 1.8 μm by area. The particulate media were removed and the dispersion of toner particles was then diluted to 2.0 percent solids with additional Isopar ®-H. A charge director and additive were added as indicated in Table 2. Image quality was determined using a Savin 870 copier as described in Example 1 using the paper described in that Example and Savin 2200 office copier paper (Savin).
TABLE 2
______________________________________
Charge
Sample Director Amount.sup.a
Additive
Amount.sup.b
______________________________________
2-A lecithin.sup.c
38 none --
2-B lecithin.sup.c
38 TIPA 42
2-C Basic Barium
92 none --
Petronate ®
2-D Basic Barium
92 EA 17
Petronate ®
______________________________________
.sup.a mg charge director per gram developer solids
.sup.b mg additive solids or pure liquid per gram developer solids
.sup.c purified grade, Fischer Chemical Co. Pittsburgh, PA
TABLE 3
______________________________________
Trans-
Reso- fer
Copy Den- lu- Effi-
Sample Paper Quality sity tion ciency
______________________________________
2-A Ex. 1 v. poor 0.4 4 30%
Savin v. poor 0.2 4 25%
2-B Ex. 1 excellent 2.4 10 100%
Savin excellent 1.4 9 93%
2-C Ex. 1 v. poor unreadable copy
37%
Savin v. poor 0.1 2 10%
2-D Ex. 1 poor 1.1 4 50%
Savin poor 0.4 5 50%
______________________________________
The procedure of Example 2 was repeated except that magenta and scarlet flushed pigment water presscakes were used as pigments instead of the Monastral ® Blue. The pigments were prepared in the following manner. To a Baker-Perkins sigma blade mixer was charged 450 grams of Mobay Quindo Magenta Presscake RV-6831 and 200 grams of mineral oil, intestinal lubricate, E. R. Squibb & Sons, Inc., Princeton, NJ. This was mixed until smooth and then an additional 200 grams of said mineral oil was added and mixed until smooth. The water was then removed by vacuum distillation. This procedure was repeated with Mobay Indofast Brilliant Scarlet Presscake R-6303. To prepare the toner 61.6 grams of the magenta flushed pigment and 10.4 grams of the scarlet flushed pigment were used. Toner with an average particle size of 1.37 μm was obtained. Basic Barium Petronate ® was used as the charge director in the amount of 37 mg per gram of toner solids. The results are shown in Table 4.
TABLE 4
______________________________________
Trans-
Reso- fer
Addi- Copy Den- lu- Effi-
tive Paper Quality sity tion ciency
______________________________________
none Ex. 1 good 1.3 10 92%
Savin.sup.a
fair 0.8 7 84%
TIPA.sup.b
Ex. 1 excellent
1.3 10 99%
Savin.sup.a
good 1.0 9 91%
______________________________________
.sup.a Savin = Savin 2200 office copier paper
.sup.b 7 mg/g developer solids
In a Union Process 1-S Attritor, Union Process Company, Akron, Ohio, was placed the following ingredients:
______________________________________
Ingredient Amount (g)
______________________________________
Copolymer of ethylene (89%)
200
and methacrylic acid (11%),
melt index at 190° C. is 100,
Acid No. is 66
Cabot sterling NS black pigment
15
L, nonpolar liquid having a
1000
Kauri-butanol value of 27, Exxon
Corporation
______________________________________
The ingredients were heated to 100° C.±10° C. and milled at a rotor speed of 230 rpm with 0.1875 inch (4.76 mm) diameter stainless steel balls for two hours. The attritor was cooled to room temperature while the milling was continued and then 700 grams of Isopar ®-H, nonpolar liquid having a Kauri-butanol value of 27, Exxon Corporation, were added. Milling was continued at a rotor speed of 330 rpm for 21 hours to obtain toner particles with an average size of 1.4 μm by area. The particulate media were removed and the dispersion of toner particles was then diluted to 1.5 percent solids with additional Isopar ®-H. To 1500 grams of the 1.5 percent material was added 35 grams of Basic Barium Petronate ® described in Example 1 and 0.5 gram of the specified additive. Image quality was determined using a Savin 870 copier as described in Example 1 using the paper indicated. The results are shown in Tables 5 and 6 below.
TABLE 5
______________________________________
Trans-
Reso- fer
Addi- Den- lu- Effi-
tive Paper Time.sup.b
sity tion ciency
______________________________________
none Ex. 1 0 1.82 8 90%
15 1.77 7 65%
Ex. 2.sup.a
0 1.24 9 66%
25 0.77 9 50%
TEA Ex. 1 0 1.57 10 98%
15 1.37 11 100%
Ex. 2.sup.a
0 1.02 9 90%
15 0.89 10 89%
EA Ex. 1 0 1.72 9 75%
15 1.65 9 70%
Ex. 2.sup.a
0 0.61 9 33%
15 0.59 10 33%
______________________________________
.sup.a Savin 220 office copier paper
.sup.b minutes
TABLE 6
______________________________________
Conductivity
Additive
Time = 0 Time = 5 Time = 10
Time = 15
______________________________________
none 34 22 14 11
TEA 65 74 83 88
EA 32 36 40 44
______________________________________
.sup.a minutes
FIG. 1 shows the conductivity of the control developer and developers of the invention containing TEA or EA over a time period of 15 minutes.
Example 5 demonstrates that mixtures of aminoalcohols are effective in improving image quality and stabliizing developer conductivity during extended imaging runs. Developers were prepared, charged, and tested as in Example 1. In Sample 5-A the additives used were 0.25 gram TIPA plus 0.05 gram TEA. In Sample 5-B the additives were 0.25 gram TIPA plus 0.25 gram 3-AP. The results are shown in Table 7.
TABLE 7
______________________________________
Con- Trans-
duc- Reso-.sup.a
fer
tiv- Den- lu- Effi-
Sample Time.sup.a
ity sity tion ciency
______________________________________
5-A 0 70 1.07 11 72%
15 60 0.85 11 69%
5-B 0 90 0.97 10 74%
15 120 0.88 11 81%
______________________________________
.sup.a minutes
Example 6 demonstrates the effect of additive concentration on conductivity.
In a Union Process 1-S Attritor, Union Process Company, Akron, Ohio, was placed the following ingredients:
______________________________________
Ingredient Amount (g)
______________________________________
Copolymer of ethylene (89%)
200
and methacrylic acid (11%),
melt index at 190° C. is 100,
Acid No. is 66
Mobay RV-6803, magenta pigment
22
L, nonpolar liquid having a
1000
Kauri-butanol value of 27, Exxon
Corporation
______________________________________
The ingredients were heated to 100° C.±10° C. and milled at a rotor speed of 230 rpm with 0.1875 inch (4.76 mm) diameter stainless steel balls for two hours. The attritor was cooled to room temperature while the milling was continued and then 700 grams of Isopar ®-H, nonpolar liquid having a Kauri-butanol value of 27, Exxon Corporation, were added. Milling was continued at a rotor speed of 330 rpm for 22 hours to obtain toner particles with an average size of 0.9 μm by area. The particulate media were removed and the dispersion of toner particles was then diluted to 1.5 percent solids with additional Isopar ®-H. To 1500 grams of the 1.5 percent material was added 40 grams of a 5.5% solution of Basic Barium Petronate ® described in Example 1 and the specified amount of EA. Image quality was determined using a Savin 870 copier at standard mode as described in Example 1 using the paper described in that Example. The extended run was conducted by running the machine in standard mode with a black target and the paper feed disconnected. The results are shown in Table 8 below and in FIG. 2 which shows the conductivity of the developers over a time period of 15 minutes.
TABLE 8
______________________________________
Con- Trans-
duc- Reso- fer
tiv- Den- lu- Effi-
EA (g) Time.sup.a
ity sity tion ciency
______________________________________
none 0 52 1.57 9 85%
15 15 2.01 7 70%
0.3 0 51 1.41 10 84%
15 42 1.45 9 80%
0.5 0 60 1.28 10 80%
15 72 1.15 11 75%
______________________________________
.sup.a minutes
This example compares the effect of an alcohol amine with the effect of the combination of an amine and an alcohol. The procedure in Example 6 was repeated except that the average particle size of the toner was 1.8 μm. The additives used are shown in the Table 9 below.
TABLE 9
______________________________________
Con-
duc- Reso-
tiv- Den- lu-
Additive
Amount.sup.c
Time.sup.d
ity sity tion
______________________________________
none -- 0 74 unreadable
15 20 0.40 10
HAl.sup.a
0.5 0 27 unreadable
15 8 unreadable
HAm.sup.b
0.5 0 70 unreadable
15 20 unreadable
HAl.sup.a +
0.25 0 32 unreadable
HAm.sup.b
0.25 15 14 unreadable
5-AP 0.6 0 42 1.56 10
15 38 1.50 10
______________________________________
.sup.a HAl = 1hexanol, purified grade, J. T. Baker, Phillipsburg, NJ
.sup.b HAm = 1hexylamine, Aldrich Chemical Co., Milwaukee, WI
.sup.c grams
.sup.d minutes
This example demonstrates that tetra(1-hydroxyethyl)ethylenediamine (THEEDA), Pfaltz and Bauer, Inc., Waterbury, Ct, improved image quality but appears to have no beneficial effect on toner stability during extended imaging runs1. Toner was prepared as described in Example 6 except that the average particle size is 0.94 μm. The toner, 1500 g of 1.5% toner, was charged with 40 g 5.5% Basic Barium Petronate ® described in Example 1 and 0.5 g additive and was evaluated in a Savin 870 copier as described in Example 1. The results are shown in Table 10 below.
TABLE 10
__________________________________________________________________________
Image Quality Time = 0 Time = 15 minutes
Trans- Trans-
Conduc- Reso-
fer Conduc- Reso-
fer
Addi- tiv- Den-
lu- Effi-
tiv- Den-
lu- Effi-
tive ity sity
tion
ciency
ity sity
tion
ciency
__________________________________________________________________________
None 68 unreadable 20 unreadable
THEEDA
78 1.03
6 100%
24 0.74
6 79%
__________________________________________________________________________
1. The extended run was conducted by running the machine in standard mode
as described in Example 1 except that the paper feed was disconnected and
a totally black target was used.
Developer was prepared in the following fashion: 7.0 g cyan pigment (Heubach, Heucophthal Blue G XBT-583D) is dispersed in 100 g polystyrene (Polysciences Polystyrene Ultrafine powder, CAT #15790) using a 2-roll mill. 40 g of this dispersion is added to a Union Process 0-1 attritor with 125 g Isopar ®-H and 125 g Isopar ®-L and ground with 0.1875 inch (4.76 mm) diameter stainless steel balls for 5 days to obtain a toner with average particle size of 1.2 μm. The toner was charged with lecithin to a level of 35 mg lecithin per gram developer solids. This developer was tested; 0.5 g TEA was added and the developer was retested. The results are shown in Table 11 below.
TABLE 11
______________________________________
Image Quality Time = 0 Time = 15 minutes
Con- Con-
duc- Reso- duc- Reso-
Addi- tiv- Den- lu- tiv- Den- lu-
tive ity sity tion ity sity tion
______________________________________
None 44 1.82 5 26 1.11 6
TEA 42 1.09 5 39 0.87 5
______________________________________
To a Union Process 1-S Attritor charged with 0.1875 (4.76 mm) carbon steel balls was added 200 g resin, 43.3 g magenta pigment (Mobay RV-6803), 23.3 g scarlet pigment (Mobay R-6300) and 1000 g Isopar ®-L. This mixture was milled at 100° C. for two hours then the Attritor was cooled with recirculating water and 700 g of Isopar ®-H and 10 g TIPA were added. The mixture was milled for 20 hours to give toner with average particle sizes ranging from 1.3 μm. The toner was diluted to 2.0% solids and to 2000 grams of this dispersion was added 60 g of 5.5% solution (diluted from 55% with Isopar ®-H) of Basic Barium Petronate ®. The toner was evaluated during extended imaging runs in a Savin 870 office copier run at standard mode as described in Example 8 using offset enamel paper as described in Example 1.
______________________________________
Image Quality Time = 0 Time = 15 minutes
Con- Trans-
Con- Trans-
duc- Reso- fer duc- Reso- fer
tiv- Den- lu- Effi- tiv- Den- lu- Effi-
ity sity tion ciency
ity sity tion ciency
______________________________________
49 1.79 6 99% 55 1.54 8 91%
______________________________________
Claims (16)
1. An electrostatic liquid developer having improved charging characteristics consisting essentially of:
(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,
(B) thermoplastic resin particles having an average by area particle size of less than 10 μm,
(C) nonpolar liquid soluble ionic or zwitterionic compound, and
(D) at least one aminoalcohol compound.
2. An electrostatic liquid developer according to claim 1 wherein the aminoalcohol is triisopropanolamine.
3. An electrostatic liquid developer according to claim 1 wherein the aminoalcohols are mixture of triisopropanolamine and triethanolamine.
4. An electrostatic liquid developer according to claim 1 wherein component (A) is present in 99.9 to 85% by weight, component (B) is present in 0.1 to 15% by weight, based on the total weight of the developer, component (C) is present in an amount of 1 to 1000 mg/g developer solids, and component (D) is present in an amount of 1 to 1000 mg/g developer solids.
5. An electrostatic liquid developer according to claim 1 containing up to about 60% by weight of a colorant based on the weight of resin.
6. An electrostatic liquid developer according to claim 5 wherein the colorant is a pigment.
7. An electrostatic liquid developer according to claim 6 wherein the percent pigment in the thermoplastic resin is 1% to 60% by weight based on the weight of resin.
8. An electrostatic liquid developer according to claim 5 wherein the colorant is a dye.
9. An electrostatic liquid developer according to claim 1 wherein a fine particle size oxide is present.
10. An electrostatic liquid developer according to claim 1 wherein the thermoplastic resin is a copolymer of ethylene and an α,β-ethylenically unsaturated acid selected from the group consisting of acrylic acid and methacrylic acid.
11. An electrostatic liquid developer according to claim 1 wherein the thermoplastic resin is a copolymer of ethylene (80 to 99.9%)/acrylic or methacrylic acid (20 to 0%)/alkyl ester of acrylic or methacrylic acid wherein alkyl is 1 to 5 carbon atoms (0 to 20%).
12. An electrostatic liquid developer according to claim 10 wherein the thermoplastic resin is a copolymer of ethylene (89%)/methacrylic acid (11%) having a melt index at 190° C. of 100.
13. An electrostatic liquid developer according to claim 1 wherein the particles have an average by area particle size of less than 5 μm.
14. An electrostatic liquid developer having improved charging characteristics comprising:
(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount.
(B) thermoplastic resin particles having an average by area particle size of less than 10 mm,
(C) Basic Barium Petronate, and
(D) at least one aminoalcohol compound.
15. An electrostatic liquid developer having improved charging characteristics comprising:
(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,
(B) thermoplastic resin particles having an average by area particle size of less than 10mm,
(C) lecithin, and
(D) at least one aminoalcohol compound.
16. An electrostatic liquid developer according to claim 1 wherein the amino alcohol is triethanolamine.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/856,392 US4702985A (en) | 1986-04-28 | 1986-04-28 | Aminoalcohols as adjuvant for liquid electrostatic developers |
| DE8787106047T DE3764857D1 (en) | 1986-04-28 | 1987-04-24 | AMINO ALCOHOLS AS ADJUVANS FOR LIQUID ELECTROSTATIC DEVELOPERS. |
| EP87106047A EP0243910B1 (en) | 1986-04-28 | 1987-04-24 | Aminoalcohols as adjuvant for liquid electrostatic developers |
| AU72105/87A AU585151B2 (en) | 1986-04-28 | 1987-04-27 | Aminoalcohols as adjuvant for liquid electrostatic developers |
| JP62102146A JPS62266566A (en) | 1986-04-28 | 1987-04-27 | Electrostatic liquid developer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/856,392 US4702985A (en) | 1986-04-28 | 1986-04-28 | Aminoalcohols as adjuvant for liquid electrostatic developers |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4702985A true US4702985A (en) | 1987-10-27 |
Family
ID=25323503
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US06/856,392 Expired - Fee Related US4702985A (en) | 1986-04-28 | 1986-04-28 | Aminoalcohols as adjuvant for liquid electrostatic developers |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4702985A (en) |
| EP (1) | EP0243910B1 (en) |
| JP (1) | JPS62266566A (en) |
| AU (1) | AU585151B2 (en) |
| DE (1) | DE3764857D1 (en) |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4780388A (en) * | 1987-05-26 | 1988-10-25 | E. I. Du Pont De Nemours And Company | Polyamines as adjuvant for liquid electrostatic developers |
| US4917985A (en) * | 1988-12-30 | 1990-04-17 | E. I. Du Pont De Nemours And Company | Organic sulfur-containing compounds as adjuvants for positive electrostatic liquid developers |
| US4923778A (en) * | 1988-12-23 | 1990-05-08 | D X Imaging | Use of high percent solids for improved liquid toner preparation |
| US4965163A (en) * | 1988-02-24 | 1990-10-23 | Fuji Photo Film Co., Ltd. | Liquid developer for electrostatic image |
| US4985329A (en) * | 1988-12-30 | 1991-01-15 | E. I. Du Pont De Nemours And Company | Bipolar liquid electrostatic developer |
| US5009980A (en) * | 1988-12-30 | 1991-04-23 | E. I. Du Pont De Nemours And Company | Aromatic nitrogen-containing compounds as adjuvants for electrostatic liquid developers |
| US5017964A (en) * | 1989-11-29 | 1991-05-21 | Am International, Inc. | Corona charge system and apparatus for electrophotographic printing press |
| US5019868A (en) * | 1989-12-28 | 1991-05-28 | Am International, Inc. | Developer electrode and reverse roller assembly for high speed electrophotographic printing device |
| US5019477A (en) * | 1989-07-05 | 1991-05-28 | Dx Imaging | Vinyltoluene and styrene copolymers as resins for liquid electrostatic toners |
| US5028508A (en) * | 1989-12-20 | 1991-07-02 | Dximaging | Metal salts of beta-diketones as charging adjuvants for electrostatic liquid developers |
| US5077172A (en) * | 1989-12-28 | 1991-12-31 | Am International, Inc. | Carrier web transfer device and method for electrophotographic printing press |
| US5177877A (en) * | 1989-12-28 | 1993-01-12 | Am International, Inc. | Dryer-fuser apparatus and method for high speed electrophotographic printing device |
| US5206108A (en) * | 1991-12-23 | 1993-04-27 | Xerox Corporation | Method of producing a high solids replenishable liquid developer containing a friable toner resin |
| US5206107A (en) * | 1991-12-30 | 1993-04-27 | Xerox Corporation | Siloxane surfactants as liquid developer additives |
| US5254424A (en) * | 1991-12-23 | 1993-10-19 | Xerox Corporation | High solids replenishable liquid developer containing urethane-modified polyester toner resin |
| US5254427A (en) * | 1991-12-30 | 1993-10-19 | Xerox Corporation | Additives for liquid electrostatic developers |
| US5304451A (en) * | 1991-12-23 | 1994-04-19 | Xerox Corporation | Method of replenishing a liquid developer |
| US5306590A (en) * | 1991-12-23 | 1994-04-26 | Xerox Corporation | High solids liquid developer containing carboxyl terminated polyester toner resin |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4702984A (en) * | 1986-04-30 | 1987-10-27 | E. I. Dupont De Nemours And Company | Polybutylene succinimide as adjuvant for electrostatic liquid developer |
| US4758494A (en) * | 1987-02-13 | 1988-07-19 | E. I. Du Pont De Nemours And Company | Inorganic metal salt as adjuvant for negative liquid electrostatic developers |
| US4859559A (en) * | 1987-03-18 | 1989-08-22 | E. I. Du Pont De Nemours And Company | Hydroxycarboxylic acids as adjuvants for negative liquid electrostatic developers |
| US4804601A (en) * | 1987-06-29 | 1989-02-14 | Xerox Corporation | Electrophotographic and electrographic imaging processes |
| US4977056A (en) * | 1987-08-10 | 1990-12-11 | E. I. Du Pont De Nemours And Company | Alkylhydroxy benzylpolyamine as adjuvant for electrostatic liquid developers |
| US4794066A (en) * | 1987-11-04 | 1988-12-27 | E. I. Du Pont De Nemours And Company | Process for preparation of liquid electrostatic developer |
| US4994341A (en) * | 1989-12-20 | 1991-02-19 | Dximaging | Organometallic compounds as mottle prevention additives in liquid electrostatic developers |
| US5266435A (en) * | 1991-12-04 | 1993-11-30 | Spectrum Sciences B.V. | Liquid toners containing charge directors and components for stabilizing their electrical properties |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3362907A (en) * | 1964-03-06 | 1968-01-09 | Australia Res Lab | Liquid developer with sharp cut-off response |
| US3417019A (en) * | 1962-12-27 | 1968-12-17 | Eastman Kodak Co | Xerographic development |
| US3528097A (en) * | 1967-03-14 | 1970-09-08 | Matsushita Electric Ind Co Ltd | Liquid developers for developing electrostatic images |
| US3844966A (en) * | 1964-02-06 | 1974-10-29 | Dennison Mfg Co | Electrostatic liquid developer composition |
| JPS51109843A (en) * | 1975-03-24 | 1976-09-29 | Hitachi Ltd | |
| JPS5428141A (en) * | 1977-08-04 | 1979-03-02 | Ricoh Co Ltd | Liquid developer for static latent image |
| US4144184A (en) * | 1977-03-07 | 1979-03-13 | Ishihara Sangyo Kaisha, Ltd. | Liquid developer |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL128027C (en) * | 1961-08-31 | 1900-01-01 | ||
| US4425418A (en) * | 1981-05-19 | 1984-01-10 | Konishiroku Photo Industry Co., Ltd. | Liquid developers for electrophotography and developing method using the same |
| US4507377A (en) * | 1982-11-19 | 1985-03-26 | Eastman Kodak Company | Self-fixing liquid electrographic developers |
| US4476210A (en) * | 1983-05-27 | 1984-10-09 | Xerox Corporation | Dyed stabilized liquid developer and method for making |
| DE3564047D1 (en) * | 1984-02-20 | 1988-09-01 | Fuji Photo Film Co Ltd | Liquid developer for electrostatic photography |
| US4702984A (en) * | 1986-04-30 | 1987-10-27 | E. I. Dupont De Nemours And Company | Polybutylene succinimide as adjuvant for electrostatic liquid developer |
| US4758494A (en) * | 1987-02-13 | 1988-07-19 | E. I. Du Pont De Nemours And Company | Inorganic metal salt as adjuvant for negative liquid electrostatic developers |
| US4780388A (en) * | 1987-05-26 | 1988-10-25 | E. I. Du Pont De Nemours And Company | Polyamines as adjuvant for liquid electrostatic developers |
-
1986
- 1986-04-28 US US06/856,392 patent/US4702985A/en not_active Expired - Fee Related
-
1987
- 1987-04-24 EP EP87106047A patent/EP0243910B1/en not_active Expired
- 1987-04-24 DE DE8787106047T patent/DE3764857D1/en not_active Expired - Lifetime
- 1987-04-27 JP JP62102146A patent/JPS62266566A/en active Pending
- 1987-04-27 AU AU72105/87A patent/AU585151B2/en not_active Ceased
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3417019A (en) * | 1962-12-27 | 1968-12-17 | Eastman Kodak Co | Xerographic development |
| US3844966A (en) * | 1964-02-06 | 1974-10-29 | Dennison Mfg Co | Electrostatic liquid developer composition |
| US3362907A (en) * | 1964-03-06 | 1968-01-09 | Australia Res Lab | Liquid developer with sharp cut-off response |
| US3528097A (en) * | 1967-03-14 | 1970-09-08 | Matsushita Electric Ind Co Ltd | Liquid developers for developing electrostatic images |
| JPS51109843A (en) * | 1975-03-24 | 1976-09-29 | Hitachi Ltd | |
| US4144184A (en) * | 1977-03-07 | 1979-03-13 | Ishihara Sangyo Kaisha, Ltd. | Liquid developer |
| JPS5428141A (en) * | 1977-08-04 | 1979-03-02 | Ricoh Co Ltd | Liquid developer for static latent image |
Non-Patent Citations (2)
| Title |
|---|
| Allen et al., "Improved Electrostatic Printing Inks", Xerox Discl. Jour., vol. 2, No. 6, Nov.-Dec. 1977, pp. 77-80 (copy 156). |
| Allen et al., Improved Electrostatic Printing Inks , Xerox Discl. Jour., vol. 2, No. 6, Nov. Dec. 1977, pp. 77 80 (copy 156). * |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4780388A (en) * | 1987-05-26 | 1988-10-25 | E. I. Du Pont De Nemours And Company | Polyamines as adjuvant for liquid electrostatic developers |
| US4965163A (en) * | 1988-02-24 | 1990-10-23 | Fuji Photo Film Co., Ltd. | Liquid developer for electrostatic image |
| US4923778A (en) * | 1988-12-23 | 1990-05-08 | D X Imaging | Use of high percent solids for improved liquid toner preparation |
| US4917985A (en) * | 1988-12-30 | 1990-04-17 | E. I. Du Pont De Nemours And Company | Organic sulfur-containing compounds as adjuvants for positive electrostatic liquid developers |
| US4985329A (en) * | 1988-12-30 | 1991-01-15 | E. I. Du Pont De Nemours And Company | Bipolar liquid electrostatic developer |
| US5009980A (en) * | 1988-12-30 | 1991-04-23 | E. I. Du Pont De Nemours And Company | Aromatic nitrogen-containing compounds as adjuvants for electrostatic liquid developers |
| US5019477A (en) * | 1989-07-05 | 1991-05-28 | Dx Imaging | Vinyltoluene and styrene copolymers as resins for liquid electrostatic toners |
| US5017964A (en) * | 1989-11-29 | 1991-05-21 | Am International, Inc. | Corona charge system and apparatus for electrophotographic printing press |
| US5028508A (en) * | 1989-12-20 | 1991-07-02 | Dximaging | Metal salts of beta-diketones as charging adjuvants for electrostatic liquid developers |
| US5019868A (en) * | 1989-12-28 | 1991-05-28 | Am International, Inc. | Developer electrode and reverse roller assembly for high speed electrophotographic printing device |
| US5077172A (en) * | 1989-12-28 | 1991-12-31 | Am International, Inc. | Carrier web transfer device and method for electrophotographic printing press |
| US5177877A (en) * | 1989-12-28 | 1993-01-12 | Am International, Inc. | Dryer-fuser apparatus and method for high speed electrophotographic printing device |
| US5206108A (en) * | 1991-12-23 | 1993-04-27 | Xerox Corporation | Method of producing a high solids replenishable liquid developer containing a friable toner resin |
| US5254424A (en) * | 1991-12-23 | 1993-10-19 | Xerox Corporation | High solids replenishable liquid developer containing urethane-modified polyester toner resin |
| US5304451A (en) * | 1991-12-23 | 1994-04-19 | Xerox Corporation | Method of replenishing a liquid developer |
| US5306590A (en) * | 1991-12-23 | 1994-04-26 | Xerox Corporation | High solids liquid developer containing carboxyl terminated polyester toner resin |
| US5206107A (en) * | 1991-12-30 | 1993-04-27 | Xerox Corporation | Siloxane surfactants as liquid developer additives |
| US5254427A (en) * | 1991-12-30 | 1993-10-19 | Xerox Corporation | Additives for liquid electrostatic developers |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0243910B1 (en) | 1990-09-12 |
| AU585151B2 (en) | 1989-06-08 |
| DE3764857D1 (en) | 1990-10-18 |
| EP0243910A1 (en) | 1987-11-04 |
| AU7210587A (en) | 1987-10-29 |
| JPS62266566A (en) | 1987-11-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4702985A (en) | Aminoalcohols as adjuvant for liquid electrostatic developers | |
| US4707429A (en) | Metallic soap as adjuvant for electrostatic liquid developer | |
| EP0244725B1 (en) | Polybutylene succinimide as adjuvant for electrostatic liquid developer | |
| US4760009A (en) | Process for preparation of liquid toner for electrostatic imaging | |
| US4631244A (en) | Process for preparation of liquid toners for electrostatic imaging using polar additive | |
| US4734352A (en) | Polyhydroxy charging adjuvants for liquid electrostatic developers | |
| US4923778A (en) | Use of high percent solids for improved liquid toner preparation | |
| US4758494A (en) | Inorganic metal salt as adjuvant for negative liquid electrostatic developers | |
| US4740444A (en) | Process for preparation of electrostatic liquid developing using metallic soap as adjuvant | |
| US4859559A (en) | Hydroxycarboxylic acids as adjuvants for negative liquid electrostatic developers | |
| US4772528A (en) | Liquid electrostatic developers composed of blended resins | |
| US4663264A (en) | Liquid electrostatic developers containing aromatic hydrocarbons | |
| EP0376305A2 (en) | Aromatic nitrogen-containing compounds as adjuvants for electrostatic liquid developers | |
| US4780389A (en) | Inorganic metal salt as adjuvant for negative liquid electrostatic developers | |
| US4681831A (en) | Chargeable resins for liquid electrostatic developers comprising partial ester of 3-hydroxypropanesulfonic acid | |
| US4783388A (en) | Quaternaryammonium hydroxide as adjuvant for liquid electrostatic developers | |
| US4670370A (en) | Process for preparation of color liquid toner for electrostatic imaging using carbon steel particulate media | |
| US4977056A (en) | Alkylhydroxy benzylpolyamine as adjuvant for electrostatic liquid developers | |
| EP0315117A2 (en) | Process for preparation of liquid electrostatic developer | |
| EP0420083A2 (en) | Metal alkoxide modified resins for negative-working electrostatic liquid developers | |
| EP0292898B1 (en) | Polyamines as adjuvant for liquid electrostatic developers | |
| US4935328A (en) | Monofunctional amines as adjuvant for liquid electrostatic developers | |
| US5382492A (en) | Quaternary ammonium compound as charge adjuvants for positive electrostatic liquid developers | |
| US4950576A (en) | Chromium, molybdenum and tungsten compounds as charging adjuvants for electrostatic liquid developers | |
| EP0397107A2 (en) | Nickel (II) salts as charging adjuvants for electrostatic liquid developers |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: E. I. DU PONT DE NEMOURS AND COMPANY, WILMINGTON, Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:LARSON, JAMES R.;REEL/FRAME:004560/0171 Effective date: 19860424 Owner name: E. I. DU PONT DE NEMOURS AND COMPANY,DELAWARE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LARSON, JAMES R.;REEL/FRAME:004560/0171 Effective date: 19860424 |
|
| FPAY | Fee payment |
Year of fee payment: 4 |
|
| FPAY | Fee payment |
Year of fee payment: 8 |
|
| REMI | Maintenance fee reminder mailed | ||
| LAPS | Lapse for failure to pay maintenance fees | ||
| FP | Lapsed due to failure to pay maintenance fee |
Effective date: 19991027 |
|
| STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |